An official death toll for the heinous attack has not yet been established but rescuers are working desperately to free those trapped under the rubble with temperatures plunging to -4 degrees C
James Heappey said the West is gathering evidence that can be used in a future prosecution, but added in interviews: What you see on your TV screens is a war crime.
The White House on Wednesday condemned what it said was the barbaric bombing of a maternity hospital in the Ukrainian city of Mariupol that left children buried in the rubble.